Dual feed-pulverizing apparatus



Oct. 15, 1929. F. H. DANN-:Ls

DUAL FEED PULVERIZING APPARATUS Filed Nov. 6, 1926 w Q 4 441%3 7 ,0 ,6JMU, w 4V llll\ 0 6 m n W imM Zu 6. m //f.w ,r 6 W .M 4 J w w L, 6 lll 2rl .M 4 5 HM l WWU d FU 0 ,zu M 1 uw f/U .w j

xNvENToR Ei'zw H. DAME-'La WITNESS @W Patented Oct. 15,- 19294 UNITEDfs-'rAres .PATENT OFFICE CORPORATION, OI' WORCESTER, MASSACHUSETTS,

SETTS A conronArroN or mssacnu- DUAL FEED-PUL'VERIZIG APPARATUSApplicationv led November 6, 1926. Serial No. 146,590.

This invention relates to a pulverizing apparatus, and more particularlyto a machine of this type which is arranged to simultaneously mix andpulverize two materials., j In burning pulverized fuel in suspension ina furnace, it is essential that the fuel contain sufficient volatilematter to cause a satisfactory rate of iiame propagation, as otherwiseit is impossible td maintain a flame. For this reason, great diicultyhas been experienced in the past in burning, after pulverization, suchfuels as anthracite, coke, and soot which contain a very low per cent ofvolatile matter. It is therefore desirable in 16 many cases to mix ahighly volatile solid ma- .terial with such fuels to insure proper combustion, and it may be advisable to change the proportions of the twoingredients from time to time as the character of one or the 20 othervaries. It is, however, diliicult and ex.4 v

pensive to mix the fuels before introduction to the pulverizer by theusual methods and apparatus, hence the users of powdered .fuel have notheretofore been able to buy various assortments of fuel and mix them aswanted Ato give a desired type of flame. The degree of uniformity ofsuch a mixture will also affect the nature of the ame, it beingdesirable to have a uniform product which does not fluctuate constantlyin its characteristics.

It moreover is found inpulverizing coal, that the capacity of thepulverizer becomes seriously limited whenever the moisture content ofthe coal exceeds a certain amount. This has made necessary in the pastthe installation and operation of expensive and bulky drying devices.Hence'it 1s often wise to mix a'drier fuel with the wet material tolower V its moisture content. This involves like problems which havebeen hard to overcome. These same considerations apply in general toother materials. It is often neces- A rovide a mixture of two pulverizedmateria s of variouschemical and physical properties, and any ap aratusor method which will carry out satlsfactorily both operations of mixingand pulverizing is cominerciallyl desirable.

It is t erefore one object of my invention to provide a simple type ofapparatus which vof the unit type, arranged to pulverize matevdependently o each other that either may move the pulverized materialand transport will mix two different materials in .desired proportionsand pulverize the same.

A further object is to provide an apparatus which will automatically mixdiferent'materials in regulatable proportions and feed them at a desiredvariable rate and then pulyerize and deliver the mixture at a rate which1s suitable for the particular material being handled and in accordancewith the use to which it is to be put. Y

With these and other objects in view as will be apparent to one skilledin the art,`

my invention resides in the combination of parts set forth in thespecification and covered by the claims appended hereto.

.In accordance with my invention, I-opro vide a pulverizing apparatuswith means for feeding two materials thereto simultaneously atregulatable rates. The pulverizer may be rial such as fuel vand deliverit directly to a. storage bin or to a furnace, if intended forcombustion purposes. The feeders, coordinated with the u lverizer, areso arranged'inbe used alone oroperated to feed a given material at adesired rate, so that two materials may be mixed 'in any suitableproportions.' These feeders are operated automatically as the ulverizingdevice 4grinds the material ,to feed the latter as needed. Coordinatedwith these feeding and grinding members isv a further mechanism, such-asa fan, to re-A it to a desired point.

vReferring to the drawings in which like y reference numerals indicatelike parts: Fig. 1 is an'end elevation of one'embodiment of myinvention, lpartsbeing shown in section; v

Fig. 2 is avertical `section through the center of the apparatus shownin F1 1, with parts broken awaylforclearness o illustra-v tion; and lFig. 3 is a horizontalsection throughone of the feeding devices.

The apparatus illustrated in the drawings comprisesv a pulverizer of therotary beater or impactty'pe having two rotary feeding tables soarranged as to feed material di- 10n rectly to the same pulverizingzone. The

specific construction of the pulverizer may be similar to the machinesdisclosed in the reissue patent to Blyth, No. 16,229, and the patent toRiley, No. 1,576,472. Such a machine may comprise a casing arranged toform a pulverizing chamber and a fan chamber 12 connected by a centraloutlet passage 14.v The pulverizing chamber may be provided with liningplates 15, 16 and 17. The fan chamber ma be provided with a lining plate18. A sha t 20 extends centrally through chambers 10 and 12, and isrotatably mounted in suitable bearings 22 and 24. This shaft is providedwith a half coupling 25, for connection to a suitable source of power.

A rotor disk 28 is mounted on the shaft 20 and arran ed to rotate inchamber 10. This disk may e provided with pegs 30 on each 20 face whichcooperate with stationary pegs 32 on the casing walls. The pegs aresuitably mounted on their supports,` as disclosed for example in thepatent to Riley. In order to withdraw ine material from the chamber 10,25 a fan 34 is mounted on shaft 20 so as to rotate in chamber 12. Thefan chamber is provided with an outlet 35. A suitable air inlet 36 ispreferably arranged in the wall of the chamber 10.

Two different materials ma?)7 be delivered to the pulverizing chamber 10y two se arate feeding devices arranged to permit t e desired regulationof the two rates of feed. These may be identical, as shown, except .thatthey are made right and left for convenience in arrangement. Eachfeeder, as illustrated,

may comprise a substantially horizontal disk shaped table 40, rotatablymounted within a caslng 41 on a vertical shaft 42. This shaft issupported in bearings 44 and 45, and is slowly rotated by a worm gear 46fixed there-- on and driven by a worm 48. Each worm may be provided witha pulley 50 and may be conveniently driven directly from the pulverizershaft 20 by a belt 52 which passes through an opening 53 in the pedestal55. A stationary hopper 56 is mounted on the casing'41 above each table40, and this hopper is provided with an opening 58 in one side.

lade 60 is provided, the lade being mounted on a short post threaded tothe upperend of shaft 42.

. The amount of material delivered through per 56, an agitatordetermined by an adj usta le scraper 61, which is supported insubstantial contact with the top surface of the table. This scraper hasa nut like portion threaded internally and mounted for adjustment on ahorizontal shaft 63 externally threaded on its intermediate portion (seeFig. 3). This shaft 63 is rotatably mounted in bearings inthe casing 41,and is prevented from longitudinal movement 65 by collars 65 and 66. Theshaft is conven- To assist in rotatinthe material in the hopthe openings58 and swe t off the table 40 is iently rotated by al handwheel 68. Bythis means, the scraper maybe moved in or out .to swee more or lessmaterial from the table. An inc ined chute is arranged to conductmaterial swept from the table 40 through opening 71 into the'pulverizerchamber. `As shown in Fig. 1, there may be two of these openin s, one ateach side of the shaft 20, for eac of the feeders.

In using this afparatus in connection with a furnace, a pipe 5 may beprovided leading from the fan discharge 35 to a burner 76 of anysuit-able type mounted adjacent to an opening in a furnace wall 78. Ifdesired, additional air may be. brou ht to the burner from a fan orother-source t rough a duct 80.

The operation of the invention will now be alpparent from the abovedisclosure. The s aft 20 is rotated by a suitable source of powerconnected to the half coupling 25. Material is placed in the hopper 56in each feeder, is rotated by the agitator 60 and table 40, and is sweptfrom the table at a desired rate by the scraper 61, which is suitablypositioned by means of handwheel 68. The material passes down chute 70and enters the chamber 10, where it is pulverized and thoroughly mixedby the action of the pegs 30 and 32. The fan 34 draws the materialaround the disk 28 and through the passage 14.' The mixture leaves thefan casing through dischar e 35. Two fuels thus acted'upon ma pass trougllli pipe 75 to burner 76, and be b own into a rnace for combustion1n suspension, as is well known to those skilled in the art.

Hence by means of this apparatus, low volatile fuels may be used -withhigh volatile fuels to obtain a satisfactory rate o flame propagation,and wet coal may be mixed with dry coal to permit the ulverizer tooperate at full capacity. Siml arly, pigments or other materials may bemixed in proper proportions and pulverized to a desired degree offineness and then delivered as desired, as for example, to a store ebin. Regulation of the positions of the fee tive amounts of materialsused. If desired, the two feeders may be em loyd to feed the Samematerial, and operat either separately ortogether. Further advantageswill be readily apparent to one skilled in the art.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. A pulverizing apparatus comprising a casing having an air lnleton.one side and an outlet pipe for the pulverized material on the -otherside thereof, revoluble members mounted in the casing between the inletand the outlet which are arranged to'pulverize the material fed thereto,means to cause air to flow through the casing to the outlet pipe andtransport 'the pulverized material from the casing, independent feedingdevices communlcating with the casing which are arranged lusuelle L tofeed different materials positively and at I n La verizing elementstherein,

a predetermined rate into the casing on the inlet side of the revolublepulverizing members, and a separate control for each feeding device soarranged as to permit a predetermined variation in the composition ofthe mixture.

2. A pulverizing apparatus comprising a casing having an inlet and anoutlet on opposite sides thereof, a set of revoluble pulverzing elementsmounted between the mlet and the outlet, a fan and withdrawing thepulverized material from the casing, and power driven feeding apparatuscommunicating with the inlet and having two separately regulatabledevices arranged to deliver different materials at predetermined ratesto the inlet side of the casino' and into contact with the samepulverizlng elements, whereby the two materials are mixed and pulverizedand thereafter withdrawn from the casing through the conduit as auniform mixture.

3. A pulverizing apparatus comprising a casing having an inlet and anoutlet, preliminary and final pulverizing elements revolubly mounted inseries therein, a fan and an outlet conduit for withdrawing thepulverized material from the zone of the final pulverizing elements,separate power feeding devices communicating with the inlet for feedingdifferent materials 1n a predetermined proportion to the preliminarypulverizlng elements, said-pulverxzing elements being arranged topulverize said materials and to mix them simultaneously, means fordriving the feeding devices at uniform rates coordinated with the rateof revolutlon of the pulverizing elements and means for separatelyregulating the feeding devices to proportion the materials as desired.

4. An apparatus for treating fuel comprising` a casing defining apulverizing chamber having an inlet and an outlet, revoluble pulaconduit from the casing to connect the outlet with a fuel burner, a fanto blow the fuel from the casing to thel burner, two power drivenfeeding devices communicating with the inlet and arranged tordeliverdifferent fuels to the pulverizing elements, separate means to regulatethe rate at which fuel is fed by each device, and means for introducingair to the casing, whereby the two fuels are mixed in predeterminedamounts, pulverized uniform mixture through the burner conduit.

Signed at Worcester, Mass., this 4th day of November, 1926.

FRED H.. DANIELS.

an outlet conduit for and transported as a

